[PATCH] powerpc/64e: Fix system call illegal mtmsrd instruction
From: Nicholas Piggin <npiggin@gmail.com>
Date: 2021-07-06 05:13:50
Subsystem:
linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Madhavan Srinivasan, Linus Torvalds
BookE does not have mtmsrd, switch to use wrteei to enable MSR[EE].
Reported-by: Christian Zigotzky <redacted>
Fixes: dd152f70bdc1 ("powerpc/64s: system call avoid setting MSR[RI] until we set MSR[EE]")
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
This wasn't caught by QEMU because it executes mtmsrd just fine on BookE
CPUs. Patching that reproduces the problem and verifies this fix.
arch/powerpc/kernel/interrupt_64.S | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/arch/powerpc/kernel/interrupt_64.S b/arch/powerpc/kernel/interrupt_64.S
index 4063e8a3f704..d4212d2ff0b5 100644
--- a/arch/powerpc/kernel/interrupt_64.S
+++ b/arch/powerpc/kernel/interrupt_64.S@@ -311,9 +311,13 @@ END_BTB_FLUSH_SECTION * trace_hardirqs_off(). */ li r11,IRQS_ALL_DISABLED - li r12,-1 /* Set MSR_EE and MSR_RI */ stb r11,PACAIRQSOFTMASK(r13) +#ifdef CONFIG_PPC_BOOK3S + li r12,-1 /* Set MSR_EE and MSR_RI */ mtmsrd r12,1 +#else + wrteei 1 +#endif /* Calling convention has r9 = orig r0, r10 = regs */ mr r9,r0
--
2.23.0